LEFLORE COUNTY, Oklahoma - A statewide effort to rid Oklahoma of outdoor marijuana growing operations has been around since 1983.  

Over the past 32 years, Oklahoma Bureau of Narcotics and Dangerous Drugs agent Howard Peters tells KFSM, the CBS affiliate in Fort Smith, they've see a dramatic drop in the number of plants found.

“Back in the early 80s, we were getting hundreds of thousands of plants. Now we’re cut down a little bit, and I think this year we have got 92,000 plants,” said Howard Peters.

Peters says they use their helicopter to spot growing operations from the sky. On Thursday, they flew over rural LeFlore County.

“We’ve had some people growing for personal use that might have five, six or seven plants.  And then we’ve had others where we have seen 10,000 plants,” said Howard Peters. 

He says marijuana plants need large amounts of water, so now many operations are moving indoors.  

“Outdoor growth is really hard to do because you're really depending on the weather to make it rain all the time,” said Howard Peters.